<span>40 20Ca this is the appropriate symbol for an isotope of calcium-42 corresponding to the isotope notation AZX</span><span />
Answer:
All atoms heavier than barium
Explanation:
In the periodic table, elements are divided into blocks. We have the;
s- block elements
p- block elements
d- block elements
f- block elements
However, immediately after Barium, we now encounter elements that have f-orbitals. Barium possesses a fully filled d-orbital. Hence after it, we see elements with 4f and 5f orbitals called the Lanthanides and actinides. The elements following the lanthanide and actinide series possess completely filled f-orbitals as inner orbitals.
Hence elements heavier than barium all possess f-orbitals.
B. carbon-13 is not an allotrope of Carbon.
Allotropes<span> are elements on the periodic table that have more than one crystalline form. </span>Isotopes<span> are atoms of the same element with the same atomic number but have a different mass number.
C-13 is an isotope of carbon, not an allotrope.</span>
Answer:
Binary compound
Explanation:
Binary compounds:
The compounds which are made up of the atoms of only two elements are called binary compounds.
For example:
The following compounds are binary:
HCl
H₂O
NH₃
HCl is binary because it is composed of only hydrogen and chlorine. Ammonia is also binary compound because it is made up of only two elements nitrogen and hydrogen.
water is also binary because it is also made up of only two elements hydrogen and oxygen.
SF₆ is binary compound because it consist of atoms of only two elements i.e, sulfur and fluorine.
